Making of James Webb Space Telescope

To find the first stars and galaxies that formed in the early universe, which are millions and even billions of light years away, the Webb telescope mirror has to be wickedly smooth

The James Webb Space Telescope, targeted for launch in 2013, is already taking an incredible journey right here on Earth.To get ready for space, the 18 mirror segments that will ultimately form the Webb telescope’s huge primary mirror are trucked from pit stop to pit stop in tandem cross-country for careful processing and polishing.The story begins in a Utah beryllium mine. Beryllium is one of the lightest of all metals, and the “stuff” of the telescope’s mirrors.

Technicians in Ohio sift and purify the gritty beryllium powder from Utah into an extremely uniform optical grade especially for the Webb mirror. Then they pour the powder in a big, flat can, apply heat and pressure, and pump out the residual gas to create a large slab called a mirror billet. They bathe the billet in acid to burn off any stainless steel stuck to the billet when the can is removed. Next they split the billet in half Oreo-cookie-style to form two mirror blanks (no cream!). These mirror blanks are the largest ever produced in beryllium.

Workers in Alabama machine the back of each blank into a honeycomb structure to make the blanks lighter without reducing stiffness. The machined ribs are less than 1 millimeter thick — almost paper cut thin!

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"Ancient City" at Peru

Archaeologists say the find could provide the missing link between the ancient cultures of the Wari people and the earlier Moche civilisation.

Newly Discovered civilization
Newly Discovered Ancient civilization

Archaeologists say the find could provide the missing link between the ancient cultures of the Wari people and the earlier Moche civilisation.

The site, near the Pacific coastal city of Chiclayo, probably dates to the Wari culture which ruled the Andes of modern Peru between the 7th and 12th Century.The once buried city showed evidence of human sacrifice. The remains of the victims were thrown over the nearby cliff

Google Inc. Interview questions

Was surfing through some blogs , and found this one interesting. Some of the questions asked by Google Inc. in their interview :

1. How many golf balls can fit in a school bus?

2. You are shrunk to the height of a nickel and your mass is proportionally reduced so as to maintain your original density. You are then thrown into an empty glass blender. The blades will start moving in 60 seconds. What do you do?

3. How much should you charge to wash all the windows in Seattle?

4. How would you find out if a machine’s stack grows up or down in memory?

5. Explain a database in three sentences to your eight-year-old nephew.

6. How many times a day does a clock’s hands overlap?

7. You have to get from point A to point B. You don’t know if you can get there. What would you do?

8. Imagine you have a closet full of shirts. It’s very hard to find a shirt. So what can you do to organize your shirts for easy retrieval?

9. This one is interesting. Every man in a village of 100 married couples has cheated on his wife. Every wife in the village instantly knows when a man other than her husband has cheated, but does not know when her
own husband has. The village has a law that does not allow for adultery. Any wife who can prove that her husband is unfaithful must kill him that very day. The women of the village would never disobey
this law. One day, the queen of the village visits and announces that at least one husband has been unfaithful. What happens?

10. In a country in which people only want boys, every family continues to have children until they have a boy. if they have a girl, they have another child. if they have a boy, they stop.What is the proportion of boys to girls in the country?

11. If the probability of observing a car in 30 minutes on a highway is 0.95, what is the probability of observing a car in 10 minutes (assuming constant default probability)?

12. If you look at a clock and the time is 3:15, what is the angle between the hour and the minute hands? (The answer to this is not zero!)

13. Four people need to cross a rickety rope bridge to get back to their camp at night. Unfortunately, they only have one flashlight and it only has enough light left for seventeen minutes. The bridge is too dangerous to cross without a flashlight, and it’s only strong enough to support two people at any given time. Each of the campers walks at a different speed. One can cross the bridge in 1 minute, another in 2 minutes, the third in 5 minutes, and the slow poke takes 10 minutes to cross. How do the campers make it across in 17 minutes?

14. You are at a party with a friend and 10 people are present including you and the friend. your friend makes you a wager that for every person you find that has the same birthday as you, you get $1; for every person he finds that does not have the same birthday as you, he gets $2. would you accept the wager?

15. How many piano tuners are there in the entire world?

16. You have eight balls all of the same size. 7 of them weigh the same, and one of them weighs slightly more. How can you find the ball that is heavier by using a balance and only two weighings?

17. You have five pirates, ranked from 5 to 1 in descending order. The top pirate has the right to propose how 100 gold coins should be divided among them. But the others get to vote on hisplan, and if fewer than half agree with him, he gets killed. How should he allocate the gold in order to maximize his share but live to enjoy it? (Hint: One pirate ends up with 98 percent of the gold.)

Any answers??

Milky Way's Central Black Hole

Recent studies have calculated the distance between our sun and the galactic center, roughly 26,000 light-years away, A pair of new long-term studies tracking the orbits of stars at the center of the Milky Way Galaxy further refine the evidence that a supermassive black hole lurks there.

Recent studies have calculated the distance between our sun and the galactic center, roughly 26,000 light-years awayA pair of new long-term studies tracking the orbits of stars at the center of the Milky Way Galaxy further refine the evidence that a supermassive black hole lurks there. The two teams of researchers used data going back to 1992 and were even able to track a full revolution of one star, known as S2, around the theorized black hole, known as Sagittarius A*, some four million times the mass of the sun.